CFD软件及源程序辅助工程流体力学课程教学的探索与实践

工程流体力学课程具有较强的理论性,涉及的知识面也较宽广,给该门课程的教与学带来较大的影响。文章针对工程流体力学课程的这些特点,结合多年来的教学实践,将CFD软件和源程序的强大数值模拟功能,引入工程流体力学课程辅助教学中,通过利用CFD软件和源程序进行数值模拟教学这一环节,探讨流体力学课程对接科研成果的教学模式。实践证明,这一模式获得了较好的教学效果。     

Non-linear dynamics analysis of in-plane motion for suspended cable under concentrated load

The non-linear equations of strings under a concentrated load were derived.The formulae of the linear frequency and the governing equation of the primary resonance were obtained by Galerkin and Multiple-dimensioned method.The reason of the loss of load in practical engineering was addressed.The bifurcation graphics and the relationship graphics of bifurcate point with concentrated load and the span length of the cable were obtained by calculating example.The results show that formula of the linear frequency of the suspended cable is different from that of the string.     

Liquid rheology study on refined rapeseed oil

The rapeseed oil extracted from the mature seeds was purified by refining processing,and the rheological characteristic analysis of the viscosity and dynamic shear rate at gradient temperatures was made.The result shows that at 20,40,60 and 80 ℃ respectively,when the shear rate gradually rises,the torque increases accordingly but its viscosity does not vary distinctly.The result suggests that when rapeseed oil is used as the raw of edible oils and industries,the working procedures at high temperature will n...     

含缺陷高聚物材料热致磁效应测量控制系统设计

设计实现一套含缺陷高聚物材料在加载过程中多场耦合的集成试验系统,能在试验时对位移、拉伸力、温度、磁场等进行多场同步测量;介绍了系统结构、硬件设计、软件设计方案与原理,对其中的关键技术进行了详细说明;对聚合物PVC板材在恒定拉伸速率下的位移、拉伸力、温度场及磁场等有效数据进行了同步采集,并在数据查看界面展示了试验结果,高聚物材料匀速拉伸时,裂口处温度会急剧升高,裂口附近磁感应强度会发生一定的变化。     

变压器的非电量保护分析

变压器的非电量保护是广泛用于35kV及以上变电站的主变保护,它直接关系着主设备的安全运行。本文重点介绍了非电量保护的保护原理、注意事项及处理方法。     

Thermomechanical coupling effect of PVC sheet with defects

Thermomechanical coupling of PVC sheet with defects under uniaxial loading at different rates and different sizes of microbores was studied.The local temperature field of the dynamic damage-rupture process zone at crack tip was surveyed with infrared thermographic sensor.Based on the irreversible thermomechanics theory,the dissipation law of deformation-heat effect during the whole process was found.Furthermore,the effect of thermoelasticity in the initial stage of extension was explained.     

基于LabWindows/CVI缓变磁场分布状态信息采集系统

提出一种基于LabWindows/CVI的缓变磁场分布状态信息采集系统。重点介绍磁像传感器的电路结构,测量原理和多元误差校正技术。提供基于LabWindows/CVI的虚拟仪器控制界面和重要程序流程图。给出了含缺陷PVC板材在拉伸载荷作用下,由于内部产生的温度梯度场和应变场,由此引起的热致磁效应分布状态曲线图和某磁体端部磁通密度分布状态的实测曲线图。     

Rheology study of supercritically extracted tea-oil

The rheological analysis on dynamic shear rate-viscosity relationship of tea-oil extracted from tea-oil tree seeds by supercritical extraction method was carried out at gradient temperatures and constant shear rate,respectively.The results show that at 20,40,60 and 80 ℃,once the shear rate increases gradually,the torque enlarges correspondingly,while the viscosity shows little difference.However,at the constant shear rate,the rising temperature results in a steady downtrend on tea-oil viscosity.This results...